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Daily briefing: Visit a huge climate experiment in the Amazon rainforest
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Invisible ink becomes visible under UV light on a silicon hand.Credit: Carson Bruns
A group of nanoscientists has developed tattoo inks that become visible only under ultraviolet light, and can be hidden again using bright visible light. The inks are made from tiny spheres of acrylic glass that contain photochromes — compounds that undergo a reversible colour change on exposure to a specific wavelength of light. The products could be used in medical tattooing, such as markers to direct radiotherapy to specific parts of the body.
Universities in the United States might soon need to pay a high fee for their international students to take a science job in the country after graduation. A proposal revealed by the administration of President Donald Trump last week would require academic institutions to foot the US$100,000 bill for ‘optional practical training’, which allows overseas students to work in the United States for up to 3 years after finishing their studies. This and other rules introduced to restrict student immigration “will obliterate the pipeline” of talent, says economist Michael Clemens.
An unprecedented deadlock among members of the Intergovernmental Panel on Climate Change (IPCC) could affect the publication of its influential climate-change report. The disagreement means that the 2028 UN climate conference (COP33) — which will include an important ‘global stocktake’ of progress — might go ahead without an up-to-date scientific basis for climate negotiations. Report timelines are typically approved in “a matter of minutes”, says climatologist and panel co-chair Robert Vautard. Oil-producing nations have been accused by some others on the panel of using the issue as a stalling tactic.
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Reference: European Council of Doctoral Candidates and Junior Researchers (Eurodoc) report
A drone captures one of the AmazonFACE ring structures being built.Credit: Lalo de Almeida/Panos Pictures
Step into the rainforest with climatologist David Lapola, whose team is doing climate science on an enormous scale. The Amazon Free-Air CO2 Enrichment Experiment (AmazonFACE), set to launch in the next few months, will spend the next decade testing the prediction that an increase in atmospheric CO2 might have a ‘fertilization effect’, fuelling plant growth and pulling more carbon from the air. That carbon might get stashed away in trunk tissue, a long-lived form of carbon storage. Or it might not — as in the case of a similar experiment in the mature eucalyptus forest of Australia. “It could be that [carbon] enters tree leaves and escapes through the soil,” says Lapola. “If that’s the case, we won’t have the response the world expects.”